Statistical thermodynamics of configurational hardening in a solid solution

Short range order hardening theory for an ordering system is extended to a clustering system within the framework of the cluster variation method of configurational thermodynamics. The correlation between the solubility and solid solution hardening is discussed for each system. Both analytic and numerical calculations suggest that the smaller the solubility is the more pronounced is the hardening. In attempting to unify the hardening behavior for both ordering and clustering systems, we propose a concept termed ‘configurational hardening’.